Control apparatus.



A. 1. HALL.

CONTROL APPAHATUSI APPLICATION FILED IuIIE e. I9I6.

1,253,235 Patented Jan. 15, 1918.

WITNESSES: INVENTOR ArhurJ. Hall.

K i ATroRNEY UNITED sTATEs PATENT oEEioE.

ARTHUR J'. HALL, 0F WILKINSBURG, PENNSYLVANIA, ASSIGNOR T0 WESTINGHOUSE ELECTRIC AND MANUFACTURING COMPANY, A CORPORATION 0F PENNSYLVANIA.

CONTROL A PP ABATUS. I

Specification of Letters Patent.

Patented Jan. 15, 1918.

Applicationled June 8, 1916. Serial No. 102.499.

To all wlmi/z, it may concern:

Bev it known that I, ARTHUR J. HALL, u subject ol the. King of ircat Britain, and a resident of Wilkinsbuig, iii the county of Allegheny and State ofleniisylvania, have invented a new and useful Iniproveinent in Control Apparatus, of which the following is a specification.

My invention relates to control apparatus and particularly to liquid rheostats.

The object of m y invention is to provide a plurality of electrodes having very small initial contact areas that are relatively' widely. separated and large final contact areas that are disposed in relatively close proximity.

In liquid rlieostats that have heretofore been proposed, the entire lower edges of the electrodes establish initial contact with' the electrolyte and, since the electrodes are of the same size and are assembled in side-by side relation, the-final areas of contact with the electrolyte are separated the sainen dis tance as theV points of initial contact. n Since the resistance to the flow of an electric curlrent through a liquid rlieostat is inversely `of initial contact of adjacent electrodes will be more Widely separated than the distance between the electrodes. A

Figure 1 of the accompanying drawing is a top plan view` of a liquid rheostat embodying my invention, and Fig. 2 is a side view, partially in section and partially 1n elevation, of the rheostat shovvn'in Fig. 1.

The rheostat shown in the drawing comprises a main electrode-containing tank 1, an auxiliary electrolyte-supply tank. 2, a valve 3 for controlling the level of the electrolyte in the tank 1, a pum 4 for supplying Aelectrolyte from the tan 2 to the tank 1 and a plurality of electrodes 5 that are disposed in side-by-siderelation within the tank 1. The valve 3 is movably mounted within an outlet port 1G and is adapted to be actuated by a rod (l that is controlled hy a suitable operating mechanism (not. shown). The lower cylindrical portion of the valve 3 closes the opening 16 and the electrolyte, which is supplied to the tank 1 from the tank 2. by the pump 4, Hows over the top and through the vhollow valve 3 to the tank 2. The level of the electrolyte therefore corresponds to the position of the valve 3. Alternate electrodesI are respectively connected to teiniinal members 10 and 11 h v conducting bars 1Q and 13. Each of the electrodes 5 comprises a rectangular top portion 7, a. tapered portion 8 and a tip 9. The tapered portions of the various electrodes terminate in points at varying distances from the ends of the electrodes and the tips 9 are secured to such points, thus arranging the tips 9 in staggered relation or substantiallv diagonal alinement across the group of electrodes. i

With the electrolyte-controlling valve 3 in the position shown inthe drawing, the liquid will rise in the tank to a level corresponding to the top of the valve 3, which is i tact of the electrode with the liquid will be separated by the distance'd, as shown in Fig. 1, whereas. when the liquid has risen to its final height, the entire Contact surface of the electrodes 5 will he immersed and the distance between contact surfaces will then be the distance d. It will be noticed also that the portions of the electrodes that are initially immersed are very small and that the surfaces of the electrodes vthat are finally immersed are relatively great. thereby providing a rheostat of considerable range.

The form and dimensions of the electrodes may obviously be changed in many respects without departing from the spiritl and scope of my invention. It is to be understood therefore, that my invention comprises all modifications which fall Within the scope of the appended claims. I claim as my invention: 1. In a liquid rheostat, the combination with a tank, of a lurality of stationary ta pered electrodes disposed in side-by-side relation in the tank, said electrodes having independent tips that are positioned in a diagonal line across said grou of electrodes.

2. In a liquid rheostat, the combination with a tank, of a plurality of stationary electrodes disposed in side-by-side relation within said tank, and independent tips for said electrodes that are positioned in staggered relation.

3. In a liquid rheostat., the combination with a tank. of a plurality of electrodes disposed in side-by-side relation, said electrodes being tapered and terminating in conducting tips that are diagonally positioned across a portion of said group of electrodes.

4. In a liquid rheostat, the combination with a tank, of a plurality of electrodes disposed in side-by-Side relation within said tank, each of said electrodes being tapered and terminating in a conducting tip that is at a distance greater than the distance betyveen electrodes from the adjacent electrode tip.

In a liquid rheostat, the combination with a tank, of a plurality of tapered electrodes each terminating in ztpoint, and a tip secured to the point of each electrode, said tips being separated a greater distance than the space between said electrodes.

6. In a liquid rheostat., the combination with a tank adapted to contain an electro` lyte and means for varying the level of the electrolyte in said tank, of a plurality of electrodes disposed' in side-by-side relation and having bottoni portions so positioned that the points of Contact ot' the electrodes with the electrolyte are relatively widely separated for one level of electrolyte and are relatively close together for another level of electrolyte 7. In a` liquid rheostat, the combination with a tank adapted to contain anelectrolyte, and means for varying the height. of the electrolyte in said tank, of a plurality of electrodes rigidly positioned within said tank in side-by-side relation. said electrodes being tapered and terminating in a tip, said tips being more widely separated than the distance between said electrodes.

In testimony whereof` I have hereunto subscribed my name this 81st. day of May, 1916.

ARTHUR J. HALL. 

